The nanoscale distribution of copper and its influence on charge collection in CdTe solar cells

Development of an operando characterization stage for multi-modal synchrotron x-ray experiments

“…In particular, the fill factor has decreased and the series resistance of the cell has increased, suggesting the contact quality of the cell has diminished during operation. This phenomenon is well-known in Cu-doped CdTe devices 3,5,[59][60][61] , and has been ascribed to Cu diffusion away from the metal-CdTe contact 43 and Cu-related acceptors reacting with chlorine in the CdTe layer to convert into donors 62 .…”

“…The atomic concentrations of the XRF maps were also quantified using the MAPS software, though these quantities are mostly limited by the probe depth of the beam in these multi-component devices 42,43 .…”

“…The XRF count rates were normalized to the upstream ion chamber count rate instead of quantified in µg/cm 2 due to significant re-absorption by the CdSeTe device layers in the plan-view measurement mode. This is discussed in greater detail elsewhere 42,43,50 . This re-absorption is especially severe for Cd and Te XRF L-lines, which makes the contrast in those maps relatively poor.…”

Multi-modal characterization of kesterite thin-film solar cells: experimental results and numerical interpretation

“…Therefore, XBIC experiments on a semiconductor device combined with modeling has been performed for a single nanowire with a 1D numerical simulation carried out using Comsol Multiphysics soware, 23 and for a single-junction, CdTe/CdS solar cell with 2D dri-diffusion modeling. 24,25 In this paper, we present the results of the multi-modal study of a CZTS solar cell cross-section by employing combined measurements of scanning X-ray analytical techniques for a correlative investigation of the structural, chemical and electrical properties of a fully functional device at the nanoscale. We support experimental data with the nite volume modeling of the XBIC signal by solving Poisson's equation and the continuity equations for electrons and holes within the 2D computational domain constructed from the XRF data.…”

“…Therefore, XBIC experiments on a semiconductor device combined with modeling has been performed for a single nanowire with a 1D numerical simulation carried out using Comsol Multiphysics software, 23 and for a single-junction, CdTe/CdS solar cell with 2D drift-diffusion modeling. 24,25…”